diff --git a/CHANGELOG.md b/CHANGELOG.md
index 72c69645..e16043a4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Improvements
 - Backup
     - new **type** field on settings to specify the Timeshift backup mode: **RSYNC** or **BTRFS**
+- Trim
+    - the dialog is now displayed before the upgrading process (but the operation is only executed after a successful upgrade)
 ### UI
     - icons, buttons and colors changes
     
diff --git a/bauh/view/qt/colors.py b/bauh/view/qt/colors.py
index c73a6068..d6c65ac1 100644
--- a/bauh/view/qt/colors.py
+++ b/bauh/view/qt/colors.py
@@ -1 +1,2 @@
 GREEN = '#91a069'
+ORANGE = '#ECB03E'
diff --git a/bauh/view/qt/history.py b/bauh/view/qt/history.py
index aebd4cf6..1a1855bf 100644
--- a/bauh/view/qt/history.py
+++ b/bauh/view/qt/history.py
@@ -7,7 +7,8 @@ from PyQt5.QtWidgets import QDialog, QVBoxLayout, QTableWidget, QTableWidgetItem
 
 from bauh.api.abstract.cache import MemoryCache
 from bauh.api.abstract.model import PackageHistory
-from bauh.view.qt.view_model import get_type_label, PackageView
+from bauh.view.qt.colors import GREEN, ORANGE
+from bauh.view.qt.view_model import PackageView
 from bauh.view.util.translation import I18n
 
 
@@ -43,7 +44,7 @@ class HistoryDialog(QDialog):
                 item.setText(str(data[key]))
 
                 if current_status:
-                    item.setBackground(QColor('#ffbf00' if row != 0 else '#32CD32'))
+                    item.setBackground(QColor(ORANGE if row != 0 else GREEN))
                     tip = '{}. {}.'.format(i18n['popup.history.selected.tooltip'], i18n['version.{}'.format('updated'if row == 0 else 'outdated')].capitalize())
 
                     item.setToolTip(tip)
diff --git a/bauh/view/qt/thread.py b/bauh/view/qt/thread.py
index b31c0713..b9029afb 100644
--- a/bauh/view/qt/thread.py
+++ b/bauh/view/qt/thread.py
@@ -213,19 +213,6 @@ class UpgradeSelected(AsyncAction):
                            read_only=True,
                            icon_path=icon_path)
 
-    def filter_to_update(self) -> Tuple[List[PackageView], bool]:  # packages to update and if they require root privileges
-        to_update, requires_root = [], False
-        root_user = user.is_root()
-
-        for pkg in self.pkgs:
-            if pkg.model.update and pkg.update_checked:
-                to_update.append(pkg)
-
-            if not root_user and not requires_root and self.manager.requires_root('update', pkg.model):
-                requires_root = True
-
-        return to_update, requires_root
-
     def _sum_pkgs_size(self, reqs: List[UpgradeRequirement]) -> Tuple[int, int]:
         required, extra = 0, 0
         for r in reqs:
@@ -284,26 +271,30 @@ class UpgradeSelected(AsyncAction):
 
         return FormComponent(label=lb, components=comps), (required_size, extra_size)
 
-    def _trim_disk(self, root_password: str, ask: bool):
-        if not ask or self.request_confirmation(title=self.i18n['confirmation'].capitalize(), body=self.i18n['action.trim_disk.ask']):
-
-            pwd = root_password
-
-            if not pwd and user.is_root():
-                pwd, success = self.request_root_password()
-
-                if not success:
-                    return
-
-            self.change_status('{}...'.format(self.i18n['action.disk_trim'].capitalize()))
-            self.change_substatus('')
-
-            success, output = ProcessHandler(self).handle_simple(SimpleProcess(['fstrim', '/', '-v'], root_password=pwd))
+    def _request_password(self) -> Tuple[bool, str]:
+        if not user.is_root():
+            pwd, success = self.request_root_password()
 
             if not success:
-                self.show_message(title=self.i18n['success'].capitalize(),
-                                  body=self.i18n['action.disk_trim.error'],
-                                  type_=MessageType.ERROR)
+                return False, None
+
+            return True, pwd
+
+        return True, None
+
+    def _ask_for_trim(self) -> bool:
+        return self.request_confirmation(title=self.i18n['confirmation'].capitalize(), body=self.i18n['action.trim_disk.ask'])
+
+    def _trim_disk(self, root_password: str):
+        self.change_status('{}...'.format(self.i18n['action.disk_trim'].capitalize()))
+        self.change_substatus('')
+
+        success, output = ProcessHandler(self).handle_simple(SimpleProcess(['fstrim', '/', '-v'], root_password=root_password))
+
+        if not success:
+            self.show_message(title=self.i18n['success'].capitalize(),
+                              body=self.i18n['action.disk_trim.error'],
+                              type_=MessageType.ERROR)
 
     def _write_summary_log(self, upgrade_id: str, requirements: UpgradeRequirements):
         try:
@@ -366,17 +357,14 @@ class UpgradeSelected(AsyncAction):
             traceback.print_exc()
 
     def run(self):
-        to_update, requires_root = self.filter_to_update()
-        
-        root_password = None
+        valid_password, root_password = self._request_password()
 
-        if not user.is_root() and requires_root:
-            root_password, ok = self.request_root_password()
+        if not valid_password:
+            self.notify_finished({'success': False, 'updated': 0, 'types': set(), 'id': None})
+            self.pkgs = None
+            return
 
-            if not ok:
-                self.notify_finished({'success': False, 'updated': 0, 'types': set(), 'id': None})
-                self.pkgs = None
-                return
+        to_update = [pkg for pkg in self.pkgs if pkg.model.update and pkg.update_checked]
 
         if len(to_update) > 1:
             self.disable_progress_controll()
@@ -432,6 +420,13 @@ class UpgradeSelected(AsyncAction):
 
         app_config = read_config()
 
+        # trim dialog
+        if app_config['disk']['trim']['after_upgrade'] is not False:
+            should_trim = app_config['disk']['trim']['after_upgrade'] or self._ask_for_trim()
+        else:
+            should_trim = False
+
+        # backup process ( if enabled, supported and accepted )
         if bool(app_config['backup']['enabled']) and app_config['backup']['upgrade'] in (True, None) and timeshift.is_available():
             any_requires_bkp = False
 
@@ -460,8 +455,8 @@ class UpgradeSelected(AsyncAction):
             updated = len(requirements.to_upgrade)
             updated_types.update((req.pkg.__class__ for req in requirements.to_upgrade))
 
-            if app_config['disk']['trim']['after_upgrade'] is not False:
-                self._trim_disk(root_password, ask=app_config['disk']['trim']['after_upgrade'] is None)
+            if should_trim:
+                self._trim_disk(root_password)
 
             msg = '<p>{}</p>{}</p><br/><p>{}</p>'.format(self.i18n['action.update.success.reboot.line1'],
                                                          self.i18n['action.update.success.reboot.line2'],
diff --git a/bauh/view/resources/locale/ca b/bauh/view/resources/locale/ca
index d650a268..03a1758a 100644
--- a/bauh/view/resources/locale/ca
+++ b/bauh/view/resources/locale/ca
@@ -80,7 +80,7 @@ action.update.success.reboot.line2=Some changes may require a system restart to
 action.update.success.reboot.line3=Restart now ?
 action.update.summary=Upgrade summary
 action.update.total_size=Update size
-action.trim_disk.ask=Optimize disc (trim) ?
+action.trim_disk.ask=Optimize disc (trim) after upgrading ?
 address=adreça
 all_files=tots els fitxers
 amount=amount
diff --git a/bauh/view/resources/locale/de b/bauh/view/resources/locale/de
index 5b4f48e6..b95c1078 100644
--- a/bauh/view/resources/locale/de
+++ b/bauh/view/resources/locale/de
@@ -80,7 +80,7 @@ action.update.success.reboot.line2=Some changes may require a system restart to
 action.update.success.reboot.line3=Restart now ?
 action.update.summary=Upgrade summary
 action.update.total_size=Update size
-action.trim_disk.ask=Optimize disc (trim) ?
+action.trim_disk.ask=Optimize disc (trim) after upgrading ?
 address=Adresse
 all_files=Alle Dateien
 amount=amount
diff --git a/bauh/view/resources/locale/en b/bauh/view/resources/locale/en
index 1216adb5..b594ccf3 100644
--- a/bauh/view/resources/locale/en
+++ b/bauh/view/resources/locale/en
@@ -80,7 +80,7 @@ action.update.success.reboot.line2=Some changes may require a system restart to
 action.update.success.reboot.line3=Restart now ?
 action.update.summary=Upgrade summary
 action.update.total_size=Update size
-action.trim_disk.ask=Optimize disc (trim) ?
+action.trim_disk.ask=Optimize disc (trim) after upgrading ?
 address=address
 all_files=all files
 amount=amount
diff --git a/bauh/view/resources/locale/es b/bauh/view/resources/locale/es
index 7800149d..0fa23bd8 100644
--- a/bauh/view/resources/locale/es
+++ b/bauh/view/resources/locale/es
@@ -80,7 +80,7 @@ action.update.success.reboot.line2=Algunos cambios pueden requerir un reinicio d
 action.update.success.reboot.line3=¿Reiniciar ahora?
 action.update.summary=Resumen de actualización
 action.update.total_size=Tamaño de la actualización
-action.trim_disk.ask=¿Optimizar el disco (trim)?
+action.trim_disk.ask=¿Optimizar el disco (trim) después de actualizar?
 address=dirección
 all_files=todos los archivos
 amount=cantidad
diff --git a/bauh/view/resources/locale/it b/bauh/view/resources/locale/it
index 0f4c86fc..169854d7 100644
--- a/bauh/view/resources/locale/it
+++ b/bauh/view/resources/locale/it
@@ -80,7 +80,7 @@ action.update.success.reboot.line2=Some changes may require a system restart to
 action.update.success.reboot.line3=Restart now ?
 action.update.summary=Upgrade summary
 action.update.total_size=Update size
-action.trim_disk.ask=Optimize disc (trim) ?
+action.trim_disk.ask=Optimize disc (trim) after upgrading ?
 address=indirizzo
 all_files=tutti i files
 amount=amount
diff --git a/bauh/view/resources/locale/pt b/bauh/view/resources/locale/pt
index 17023f2f..a1e763b0 100644
--- a/bauh/view/resources/locale/pt
+++ b/bauh/view/resources/locale/pt
@@ -80,7 +80,7 @@ action.update.success.reboot.line2=Algumas alterações podem exigir a reinicial
 action.update.success.reboot.line3=Reiniciar agora ?
 action.update.summary=Resumo de atualização
 action.update.total_size=Tamanho da atualização
-action.trim_disk.ask=Otimizar disco (trim) ?
+action.trim_disk.ask=Otimizar disco (trim) depois de atualizar ?
 address=endereço
 all_files=todos os arquivos
 amount=quantidade
diff --git a/bauh/view/resources/locale/ru b/bauh/view/resources/locale/ru
index cfbe6331..bbc5bc8e 100644
--- a/bauh/view/resources/locale/ru
+++ b/bauh/view/resources/locale/ru
@@ -80,7 +80,7 @@ action.update.success.reboot.line2=Some changes may require a system restart to
 action.update.success.reboot.line3=Restart now ?
 action.update.summary=Сводка обновления
 action.update.total_size=Update size
-action.trim_disk.ask=Optimize disc (trim) ?
+action.trim_disk.ask=Optimize disc (trim) after upgrading ?
 address=Адрес
 all_files=Все файлы
 amount=amount
diff --git a/bauh/view/resources/locale/tr b/bauh/view/resources/locale/tr
index 9470b884..5a0d7d98 100644
--- a/bauh/view/resources/locale/tr
+++ b/bauh/view/resources/locale/tr
@@ -80,7 +80,7 @@ action.update.success.reboot.line2=Bazı değişiklikler, sistemin etkinleşmesi
 action.update.success.reboot.line3=Şimdi yeniden başlat ?
 action.update.summary=Yükseltme özeti
 action.update.total_size=Güncelleme boyutu
-action.trim_disk.ask=Diski optimize edin (trim) ?
+action.trim_disk.ask=Diski optimize edin (trim) after upgrading ?
 address=adres
 all_files=tüm dosyalar
 amount=miktar